CONCORD, N.H. — The New Hampshire home where a tax-evading couple staved off arrest for nine months was defended by concrete walls, homemade bombs, 60,000 rounds of ammunition and the zealousness of a few fellow believers, testimony and prosecution documents show.

Four supporters of Ed and Elaine Brown have been sent to prison for helping the couple resist efforts to arrest them since their convictions on tax-related felonies in January 2007. The Browns threatened violence if federal agents came onto their Plainfield property to arrest them, and authorities said the four supporters made similar threats, as well.

On Tuesday, one of those supporters, Daniel Riley, 40, of Cohoes, N.Y., received a 36-year prison term that includes a mandatory 30 years for making and using a destructive device in a crime of violence.

Among the explosive devices prosecutors say were seized on the Browns' property were nine homemade antipersonnel mines intended to fire shotgun shells from trees when approaching marshals hit tripwires. Prosecutors said Riley built those mines and brought in a rifle.

"Those devices, also known as spring guns, were designed exclusively to kill U.S. deputy marshals attempting to arrest the Browns," U.S. Attorney Thomas Colantuono said in a statement Tuesday.

Marshals posed as supporters
The Browns' willingness to entertain anti-government supporters at their home proved to be their undoing. Marshals posed as supporters to get onto the property and arrested them without incident in October 2007.

The Browns are now serving terms of more than five years in prison for avoiding income taxes, which they consider illegitimate, on $1.9 million of income between 1996 and 2003.

Authorities said after their arrests that the Browns would likely face charges resulting from the standoff. But Colantuono's office declined to comment Wednesday on the prospect of new charges.

Authorities say federal agents spent five days clearing the property of explosives last year so it could be searched safely.

The solar- and wind-powered home had concrete walls and clearings creating a defensible perimeter, according to testimony and prosecution documents.

Prosecutors say agents seized from the property 22 pipe bombs; semiautomatic, assault-type rifles strategically placed throughout the house; 60,000 rounds of ammunition; metal cans of gunpowder with fuses or ready to accept fuses, some wrapped in nails intended to become shrapnel; and the tree-placed mines that Riley built.

'Threat was clear'"The threat was clear, it was imminent and it was lethal," Assistant U.S. Attorney Arnold Huftalen said Wednesday.

Riley bought one of two 50-caliber, high-powered rifles with effective ranges of more than a mile to defend the house, prosecutors said. Huftalen said authorities seized night vision scopes and both armor-piercing and incendiary ammunition for the rifles.

Colantuono said he hopes Riley's long sentence will be a message "that anyone who threatens to injure or kill law enforcement officers who carry out the orders of our courts, and who enforce our laws, will be prosecuted to the full extent of the law."

Other small canisters of explosives were found in trees, placed so they could be detonated by marksmen shooting from the house, Huftalen said. Riley bought two cases of the explosive compound, harmless until its two ingredients are mixed, and took them to Plainfield, according to the government.

Supporters sentenced
In addition to Riley, other supporters convicted of aiding the Browns were Jason Gerhard, of Brookhaven, N.Y., who was sentenced to 20 years in prison, and Cirino Gonzalez of Alice, Texas, who was sentenced to eight years.

Robert Wolffe, of Randolph, Vt., was sentenced to 30 months after pleading guilty to two counts of conspiracy and being an accessory after the fact. Wolffe had cooperated with prosecutors and testified against Gerhard, Riley and Gonzalez at trial.

Riley's sentencing was delayed this summer for a mental health evaluation, part of which became public at Tuesday's hearing, the Concord Monitor reported. Riley was deemed capable of participating in his defense despite a personality disorder, the paper said.

Riley cooperated with Sven Wiberg, his court-appointed lawyer, during his trial, but since has tried repeatedly to fire him. Riley accuses Wiberg of being a federal employee colluding with other government agents against him.

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